Water Pump

"Good Evening, I have a '8

"Good Evening, I have a '84 Evinrude 90 hp. Have and overheating problem at higher speeds (3/4-full throttle.) Pulled lower unit to rebuild water pump. Impeller looked good still flexable, no cracks. Tried to change anyway, couldn't get free from drive shaft. Only replaced upper housing and seals. On reassembly, noticed that the water pipe through midsection slightly nicked on edge and not round. Fixed water pipe, and reassembled but not sure I got a good seal between pump housing and water pipe. Will redo, any advice to ensure good seal? Thanks in advance."

"First get the impeller change

"First get the impeller changed!
It is held by a wedge key. Hold the impeller with a wise grip or similar, then counter turn the drive shaft to free the wedge. If that does not work, cut the hub of the impeller.
After impeller change, take down and change thermostats and double check pressure valves that they do not stick.
It may pay off to change the big rubber seal between lower gearcase and exhaust tube as well."

"Actually I did notice that th

"Actually I did notice that the rubber seal at the exhaust tube was messed up at some point previously and needs to be changed. Couldn't get part this weekend and needed to run to check for water in lower unit oil, so reassembled and ran today. Also where would I find pressure valve and thermostats?"

"Behind the housing where the

"Behind the housing where the 2 hoses comes from the heads. Might be a bit tricky. Be sure to have all gaskets etc at hand, don't break the screws when removing. Springs a bit tricky but use tie-straps to keep together when assembling.
Pos #30 is the big rubber seal mentioned earlier. If leaking exhaust goes into pump.
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